At least three people were hospitalized with severe burns after an explosion ripped through a beer club in Hanoi early Monday, apparently due to a cooking gas leak.

The explosion happened at 5 a.m. at the O2 beer club on Cau Giay District’s To Hieu Street while it was closed.

Do Thi Han, the owner of a scrap material shop adjacent to the beer club’s kitchen, said the fire blew out her windows and injured three members of her family, including her son Do Van Canh, her daughter-in-law Hoang Mai Huong and their two-year-old Do Tien Dung.

“The blast blew them off the bed. I called a taxi to take them to the Saint Paul Hospital,” she said.

An employee at the beer club said he was sleeping with six others on the second floor when he heard the explosion.

“We climbed to the roof of an adjacent house and one of us suffered minor injuries due to a broken window,” he said.

The explosion destroyed most of the furniture in the facility, peeling off tiles and breaking windows. A traffic light outside the club was also bent in the incident.

Nguyen Anh Tuan of Cau Giay District firefighting police said the explosion was likely caused by leaking gas because there was a single blast and no fire.